(5.3×3.75+3.75×3.5)÷2.2
=3.75x(5.3+3.5)÷2.2
= 3.75x8.8÷2.2
=3.75x4
=(3又3/4)x4
=15
9.6÷(4.8×7.2+2.8×4.8)
=9.6÷4.8×(7.2+2.8)
=2×10
=20
(5.3×3.75+3.75×3.5)÷2.2
=3.75x(5.3+3.5)÷2.2
= 3.75x8.8÷2.2
=3.75x4
=(3又3/4)x4
=15
9.6÷(4.8×7.2+2.8×4.8)
=9.6÷4.8×(7.2+2.8)
=2×10
=20